A cohort effect is the particular impact of a group bonded by time or common life experience (Scott, p. 175). Cohorts in organizations are often defined by entry date, and retain some common characteristic (size, cohesiveness, competition) that can affect the organization (p. 175). For example, cohort effects are critical issues in engineering schools. Incoming students often pick their degree program based on the current job market. This can create dramatic swings in departmental class size as students chase the job demand curve, creating variable, unpredictable exigencies on faculty and administration.
Cohort effects are important to resource dependency theorists when these
groups affect structures of influence in organizations (Pfeffer, 1992).
Large, new cohort groups create training dependencies of experienced employees.
As they gain experience and compete for managerial positions, the politics
of resource control become even more important. Finally, the values of
particular cohorts can also affect the organizational culture as they reach
higher levels of influence and mentorship.